Frozen sea may harbour Mars life

Elysium's frozen sea may be one of the best places to look for life

A frozen sea found on Mars is one of the most promising places to look for life on the Red Planet, scientists say.
But planned missions designed to search for microbes below the Martian surface will not drill deep enough to find living cells, the UK team has said.

Researchers at University College London say that microbes in the first couple of metres of Martian soil would be killed off by intense radiation.

Life might survive deeper down, where conditions are more benign, they think.


It just isn't plausible that dormant life is still surviving in the near-subsurface of Mars
Lewis Dartnell, UCL
But these depths were beyond the reach of drills envisaged for missions to Mars, said Lewis Dartnell, from UCL's Centre for Mathematics and Physics in the Life Sciences & Experimental Biology (Complex).

These missions - such as Europe's ExoMars rover - could find hints that life once existed there - such as proteins, DNA fragments or fossils, explained Mr Dartnell; and that "would be a major discovery in itself".

But he added: "The Holy Grail for astrobiologists is finding a living cell that we can warm up, feed nutrients and reawaken for study.

"It just isn't plausible that dormant life is still surviving in the near-subsurface of Mars - within the first couple of metres below the surface - in the face of the ionizing radiation field.

"Finding life on Mars depends on liquid water surfacing on Mars, but the last time liquid water was widespread on Mars was billions of years ago."

Survival times

The study, published in the journal Geophysical Research Letters, maps out the likely cosmic radiation levels at various depths, taking into account different surface conditions on Mars.

Unlike Earth, Mars is not protected by a global magnetic field or thick atmosphere and for billions of years it has been laid bare to radiation from space.

Exomars rover Image: Esa
Can Europe's rover drill deep enough to find life?
Mr Dartnell's calculations suggest survival times near the surface reach only a few million years. This would mean that the chance of finding life with the planned probes is slim.

Scientists would need to dig deeper and target very specific, hard-to-reach areas such as recent craters or areas where water has recently surfaced.

The research suggested that one of the best places to look for living cells on Mars would be within the frozen sea in Mars' near-equatorial Elysium region.

This is because the ice is relatively recent - it is believed to have surfaced in the last five million years - and so has been exposed to radiation for a relatively short amount of time.

Icy secrets

Water provides an ideal shield of hydrogen to protect life on Mars from destructive cosmic radiation particles.

Ice also holds an advantage because it is far easier to drill through than rock.

But, even here, surviving cells might be out of the reach of proposed drills. Other ideal sites include recent craters, because their surfaces have been exposed to less radiation, and the gullies recently discovered in the sides of some of these craters, as they are thought to have flowed with water in the last five years.

The discovery of a vast frozen sea just below the Martian surface was announced by scientists in 2005.

Their assessment was based on pictures from Europe's Mars Express that showed plated and rutted features across an area 800km by 900km.

John Murray, from the Open University, Jan-Peter Muller, from UCL, and others said a catastrophic event probably flooded the landscape five million years ago. The floodwaters then froze out and were covered with dust or ash, they argue.

Some researchers point to the lack of "ground truth" about the radiation environment on Mars' surface to assess life's chances there.

Dog-owners 'lead healthier lives'

If you want to live a healthier life get a dog, research suggests.

The companionship offered by many pets is thought to be good for you, but the benefits of owning a dog outstrip those of cat owners, the study says.

A psychologist from Queen's University, Belfast, said dog owners tended to have lower blood pressure and cholesterol.

Writing in the British Journal of Health Psychology, she says that regular 'walkies' may partly explain the difference.

Dr Deborah Wells reviewed dozens of earlier research papers which looked at the health benefits of pet ownership.

In some cases, the social support offered by an animal is greater than the support than another human could offer Dr June McNicholas Health psychologist

She confirmed that pet owners tended in general to be healthier than the average member of the population.

However, her research suggested that dog ownership produced more positive influence than cat ownership.

As well as lower blood pressure and cholesterol, she said dog-owners suffered fewer minor ailments and serious medical problems.

There was also the suggestion that dogs could aid recovery from serious illnesses such as heart attacks, and act as 'early warning' to detect an approaching epileptic seizure.

Stress-busting

Dr Wells said the precise reason for the benefits was not totally clear.

"It is possible that dogs can directly promote our well-being by buffering us from stress, one of the major risk factors associated with ill-health.

"The ownership of a dog can also lead to increases in physical activity and facilitate the development of social contacts, which may enhance both physiological and psychological human health in a more indirect manner."

Dr June McNicholas, a health psychologist who has specialised on research into the health effects of pet ownership said that an important reason for the improved health of dog-owners was not just the exercise received while taking it for walks, but the opportunity for social contact with other dog-owners.

She said: "For older people, an animal can fulfil the 'need to be needed', perhaps after children have left home.

"In some cases, the social support offered by an animal is greater than the support than another human could offer."

Indian capsule returns from space

The rocket carrying the capsule was launched on 10 January

India says it has successfully tested the technology which ensures the safe return of astronauts from space after an orbiting capsule returned to Earth.

The capsule splashed down in the Bay of Bengal off the east coast after 11 days orbiting the earth, the Indian Space Research Organisation (Isro) said.

Isro chief Madhavan Nair said it was a key step in India's plan to send an unmanned mission to the moon in 2008.

The test's success also paves the way for future manned missions, he said.

Crucial phases

An Indian-built rocket launched the 500kg satellite, Space Capsule Recovery Experiment, and three other satellites, from Sriharikota in the southern state of Andhra Pradesh on 10 January.

The coastguard was in the process of recovering the space capsule, Isro confirmed.

The BBC's Habib Beary in Bangalore says the re-entry and recovery phases of a spacecraft are essential for any manned mission to space.

With the success of the experiment India joined the select club of nations - the US, France, Russia, China and Japan - who have mastered the technology.

Last July India failed to launch its heaviest communications satellite and test-fire its longest-range nuclear-capable ballistic missile.

Valiant Murray succumbs to Nadal

World number two Rafael Nadal held off a lion-hearted performance from Scotland's Andy Murray to reach the Australian Open quarter-finals.

Nadal battled to a 6-7 (3-7) 6-4 4-6 6-3 6-1 victory to set up a last eight meeting with Fernando Gonzalez.

Murray claimed an enthralling opening set on the tie-break, but dropped off the pace as Nadal won the second set.

The Scot won the next set but paid the price for not converting break points as Nadal took the fourth and fifth.

Highlights: Murray ousted by Nadal
Interview: Andy Murray

The players' body language at the start of the match made for fascinating viewing as they came together at the net like two boxers receiving their instructions before a title fight.

Nadal was a bundle of energy, jogging on the spot as he tried to make eye contact with his opponent, while Murray looked nervous and avoided the Spaniard's gaze.

But when the action got under way at the Rod Laver Arena, Murray stood toe-to-toe with the French Open champion.

Every service game was held in the opener, although Murray did have to save one break point before forcing the tie-break.

And Murray rose to the challenge brilliantly as he took it 7-3 thanks to an awesome serve and two correct Hawkeye challenges.

Both players went for a "comfort break" at the end of the set, but it was Murray who looked the more comfortable on their return as he held the next game to love.

Rafael Nadal
Nadal had too much strength for Murray in the final set

Murray went from strength to strength as he secured a break to claim a commanding 4-1 lead.

But Nadal, far too good a player to stay in the doldrums for long, suddenly found his best form, winning the next five games in a row to turn the set on its head.

Murray's serve fell apart as he seemed to struggle with a side strain.

And his malaise carried over to the start of the third set as two double faults in succession handed Nadal another break and a 3-1 lead.

But with his prospects looking bleak, Murray turned things around in astonishing style as he broke back before snatching the set with another break in the 10th game.

With the clocks ticking well past midnight in Melbourne, a rejuvenated Murray held serve twice


606: DEBATE
No disgrace in Murray losing to the world No.2, especially as he took 2 sets

SG
606: Have your say

But a crucial turning point came in the fourth game of the set as five break points came and went for Murray, allowing Nadal to hold for a vital psychological boost.

Nadal took full advantage of the let-off, breaking twice to set up a final-set decider.

The fifth set proved a let down for Murray and his enthusiastic band of followers but it could have all been different had Murray managed to convert the break points that came his way.

Instead it was Nadal who took his chances on Murray's serve to give a cruel twist to the scoreline which the 19-year-old's brave performance did not deserve.

First stars in telescope's sights

The Hubble Space Telescope is a hard act to follow.

Since it was launched in 1990, the telescope has become one of the most important instruments in the history of astronomy, making critical discoveries that have vastly enriched our understanding of the cosmos.

John Mather is only too aware of this legacy. He is senior project scientist on Hubble's designated successor, the James Webb Space Telescope (JWST).

Dr Mather, 60, has been involved with JWST from the start and is busy directing construction of it at Nasa's Goddard Space Flight Center in Maryland.

He is also a Nobel Laureate - Nasa's first. Mather shared the 2006 Nobel Prize in Physics with George Smoot for their work on the Cosmic Background Explorer (Cobe) satellite.

Everybody needs the successor to Hubble. If it were not here, people would be moaning and crying into their beer every day John Mather, JWST senior project scientist

Cobe detected subtle temperature variations in the cosmic microwave background radiation - the "afterglow of the Big Bang".

These variations pointed to the density differences that ultimately gave rise to the first galaxies and stars, something Stephen Hawking called "the most important discovery of the century, if not of all time".

Speaking to BBC News at the American Astronomical Society's winter meeting in Seattle, Dr Mather said there were great expectations for JWST from the astronomical community and the public.

"Everybody needs the successor to Hubble. If it were not here, people would be moaning and crying into their beer every day. So we know that we have to have something," he explained.

"It was identified as the top priority for the nation - so we're doing it."

Click here to see JWST's main components

Red light

But the James Webb Space Telescope, named after a former administrator of Nasa, is not going to repeat the science carried out by its predecessor.

While Hubble gazed at the Universe in optical and ultra-violet wavelengths, JWST will look primarily in the infrared.

"This telescope extends the science that Hubble has pioneered, but it covers different wavelength regions," Dr Mather said.

"The infrared is where the new science seems to be, and where this mission has a special and unique advantage."

Hubble will be a tough act to follow

Infrared astronomy is particularly important for understanding about the processes that went on in the early Universe.

Distant objects in the Universe are moving away from us at very fast speeds - and this has an interesting effect on the light they emit. It gets shifted to longer wavelengths: the "red" part of the spectrum.

The infrared is therefore essential to seeing the farthest - and therefore the earliest - objects to form in the Universe, a consideration that was one of the most important driving factors behind the design of the telescope.

"We know what the theories are predicting about these early objects, we know how bright and how far away they are supposed to be and what kind of telescope it would take to see them," said John Mather.

"So we said, 'it can't be a small telescope, it has to be a big one, and it has to work at certain infrared wavelengths'."

Eagle Nebula: In the infrared (L) and at Hubble's visible wavelengths

Infrared wavelengths are also good for seeing through the cocoons of dust that often obscure stars and planets in the process of formation.

But infrared light does not penetrate the Earth's atmosphere very well. This was one reason why an infrared telescope was needed in space, says Dr Mather.

In addition, the telescope needs to be cold, otherwise it will emit its own infrared radiation, swamping faint astronomical signals.

"It's designed to operate at cryogenic temperatures, on the order of 40 Kelvin (-233C, -388F)," said Dr Mark Clampin, observatory project scientist for JWST.

The technology builds on what we've done with Hubble, but takes it to the next level Mark Clampin, observatory project scientist, JWST

"By doing that, we get the background of the telescope down so that we're looking at red light coming from the early Universe."

The large shield that visually dominates the spacecraft is designed to block light from the Sun, Earth and Moon that would otherwise heat up the telescope.

For this to work, it cannot be put in low-Earth orbit like Hubble. It must be in an orbit where all three of these objects are in about the same direction.

The most convenient place is "L2", one of five gravitational balance points in space, where it can stay fixed in the same spot relative to the Earth and the Sun.

JWST's primary mirror will be 6.6m (22ft) in diameter, compared with Hubble's 2.4m (7.9ft) mirror.

This is important because it determines the amount of light the telescope can collect, and therefore its ability to detect dim objects.

Performance tweak

"Hubble is a conventional telescope. It has a 2m primary mirror with a secondary mirror. JWST has a segmented primary mirror comprised of 18 individual elements," said Mark Clampin.

JWST's mirror will be much bigger than Hubble's

"It gives us a lot more flexibility during its lifetime because we can actually tweak up the performance of the telescope.

"A lot of the technology builds on what we've done with Hubble, but takes it to the next level."

Although its primary mission is due to last five years, it is hoped this will be extended as it has been again and again in the case of Hubble.

It is even possible that when Nasa's new manned vehicle, the Crew Exploration Vehicle (CEV) enters use, JWST could be serviced to upgrade it and extend its life.

The mission aims to examine every stage in cosmic history and the science priorities are organised into four main themes:

• the end of the cosmic "Dark Ages"
• the assembly of galaxies
• the birth of the first stars and protoplanetary systems
• planetary systems and the origin of life

"We think we know the initial conditions of the Universe now, at least in a statistical way," said John Mather.

"We have international agreement that our theories work up until the first stars start to form. The minute that interesting things start to happen, that stars light up and galaxies are forming, then all of those theories are no longer sufficient.

"We get into the complexity of immense chaotic processes. It's like going from climate prediction to tornado prediction."

Cosmic digging

Many aspects about the formation of the first stars are unknown, as are the processes by which the earliest clusters of stars started to organise themselves into galaxies like our own Milky Way.

"We'd like to do cosmic archaeology," said John Mather.

"Astronomers are lucky in the sense that we can see things as they were by looking very far away. Light travels so slowly that it takes a long time to get here from those distant objects.

"People think that light travels fast. But for cosmologists, it's just the right speed. It lets us look back into the earliest Universe if we can build the right kind of telescope."

We just know we can do more with something better John Mather

JWST should also be able to detect extrasolar planets through the transit technique and examine the formation of planetary systems, a puzzle that has occupied astronomers for more than 50 years. And it even aims to shed light on the origins of life.

"We may be able to see something about the atmospheric chemistry of planets. If the planet's small enough, we may be able to learn about organic chemistry on an Earth-like object," said John Mather.

"We need luck on this one. We need people to go and survey all the nearby stars for planets and select the best targets. Maybe we'll get lucky."

Tough times

The project has survived through some turbulent times at Nasa.

As the agency has been re-structured to pay for President Bush's Vision for Space Exploration - which involves returning humans to the Moon by 2020 - science budgets have been slashed, resulting in many robotic missions being dropped.

JWST has been protected, partly through the patronage of influential executives within Nasa.

The telescope is due to launch on a European Ariane 5 from Kourou in 2013. With its tennis court-sized sunshield and huge mirror, JWST is so big it has to be folded up to get it into the rocket fairing.

The process of unfurling it in space is extremely complicated, and engineers are modelling this through computer simulations.

"Once we get to orbit, we first put out the transmitter and solar panels," said Mark Clampin.

"Then we deploy the sunshield so we can protect the primary mirror, then we unfold two wings with additional segments for the primary mirror, followed by the secondary mirror."

"It's very different from anything that's been done in the past."

Dr Mather said: "It's an elaborate process, but a butterfly comes out of the cocoon and unfolds its wings."

He said he hoped the telescope would eventually prove as important to astronomy as Hubble has been.

"Hubble has been so brilliantly successful," he said, "and we just know we can do more with something better."

THE JAMES WEBB SPACE TELESCOPE JWST is named after James E Webb, Nasa Administrator during the Apollo lunar exploration era; he served from 1961 to 1968 It will be placed 1.5m km from Earth, at Lagrange Point 2, an area of gravitational balance between the Earth and the Sun The telescope will be shaded from sunlight by a shield, enabling it to stay cold, increasing its sensitivity to infrared radiation Three principal instruments will gather images of the Universe in the infrared region of the spectrum These will yield new information about how stars and galaxies first formed a few hundred million years after the Big Bang

Lung cancer vaccine to be tested

A large-scale trial to test a vaccine against the most common form of lung cancer has been launched.

More than 1,300 patients worldwide will help test Stimuvax, which in preliminary trials substantially increased survival time for many.

There were more than 37,000 people diagnosed with lung cancer in the UK in 2003, and death rates remain high.

The vaccine works by stimulating the body's own immune system to attack cancer cells.

It is aimed at the non-small cell type of lung cancer, which accounts for four-fifths of cases in the UK.

Currently, patients receive combinations of surgery, chemotherapy and radiotherapy.

Targeted vaccines are an exciting approach that could potentially offer new treatment options for major types of cancer Dr Keith Blundy Cancer Research Technology

Half of the people taking part in the worldwide trial will get this treatment, plus the vaccine, while the other half will get just the treatment, and a dummy vaccine called a placebo, so that scientists can compare survival in the two groups.

The vaccine was developed following research funded by Cancer Research UK, and the technology was licensed to be developed by Canadian biotech firm Biomira.

Dr Keith Blundy, chief operating officer of Cancer Research Technology, the charity's commercial arm, said: "Targeted vaccines are an exciting approach that could potentially offer new treatment options for major types of cancer."

Other researchers are looking at the potential for the same vaccine to tackle other types of cancer.

It works by priming the body's immune system to attack a chemical called MUC-1, which is found only on the surface of cancer cells.

Once this has happened, the body should be able to destroy cancer cells while leaving healthy cells unaffected.

Survival time 'increased'

Smaller-scale trials, involving 171 patients who had responded to conventional treatment, suggested that the vaccine might be helping some patients in their fight against the cancer.

Again, half the patients received normal treatment plus the vaccine, half got treatment and a dummy vaccine.

The patients were then monitored as they returned for check-ups over the next few years.

In the placebo group, half the patients survived 13 months or longer. In the vaccine group, half survived 30 months or longer.

If these large-scale trials yield similarly positive results, the vaccine could eventually be made more widely available to lung cancer patients.

Harpal Kumar, the chief operating officer of Cancer Research UK, said: "The 'translation' of basic research into patient benefit is the major focus of our work and we hope that new ventures will lead to many more such drugs entering trials in the future."

avast! 4 Professional Edition

avast! 4 Professional Edition
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Shah Rukh Khan in 'Dhoom 3'

The latest buzz in the industry is that King Khan will act in the third edition of the Yash Raj film ‘Dhoom’.

Bollywood is going to experience part III of a movie for the very first time. After Dhoom and Dhoom2, Aditya Chopra of Yash Raj Films has announced Dhoom3. The concept of two parts of a movie or the sequel of the movie after its success is not a new one. This concept can be seen in Nagin and Nageena, Koi Mil Gaya - Krrish, Munna Bhai MBBS - Lage Raho Munna Bhai, Hera Pheri - Phir Hera Pheri etc. Aditya Chopra's decision of making Dhoom3 may lead to a new trend in bollywood.

Part I of the sequel Dhoom was a super duper hit movie, the Sanjay Gadhavi directed movie was a new concept and the movie has started the craze of racing bikes among youngsters. This has raised the sale of power bikes and even bike modiers have made good money out of the craze. After the immense success Aditya Chopra has decided to produce Dhoom2 sequel of the movie Dhoom. Dhoom2 is big budget movie which is not even released and is in news, and stands top on the list of awaited movies. Before the release of Dhoom2, Aditya Chopra is confident about the success of the movie and has announced the third part of the sequel Dhoom3. One interesting about the movie is Shahrukh Khan who is playing the role of a lover guy for Yash Raj Films, will be seen in negative role in the movie. His name has also been decided Rahul/ Mr R.

After charming John Abraham in Dhoom and handsome Hrithik Roshan in Dhoom2, Shahrukh Khan will be playing the role odd main villan in Dhoom3. Even before the release of Dhoom2, Dhoom3 has been anounced and this time Aditya Chopra has selected Shahrukh Khan as villan. His name has also been decided for the movie, Rahul/Mr. R.

Shahrukh has done lover guy kind of roles for Yash Raj films in the movies Dilwale Dulhania Le Jayenge, Dil to Pagal Hai and Mohabatein, and all these movies were superhits and Shahrukh has been awarded as best actor award for the movies. After doing lot of lover guy roles for Yash raj Films banner, and this time he will can be seen in a negative role, after Bazigar, Darr and DON.

Ranbir Sonam Jodi

Ranbir Kapoor and Sonam Kapoor can be seen opposite each other for the second time in the movie Dhoom3, before this they are working in there debut movie Sanwariya. Ranbir Kapoor the son of Rishi Kapoor and Sonam Kapoor the daughter of Anil Kapoor are good friends and they enjoy working together. They are quite lucky, that they have got a chance to work with Yash Raj Films in there second film, it is not an easy task to get a chance to work with the banner, somepeople are looking for a chance from years, and they are not getting it.

One important thing about there character is they both are playing negative role in the movie along with Shahrukh Khan.

A Reason Why Video Games Are Hard To Give Up

Kids and adults will stay glued to video games this holiday season because the fun of playing actually is rooted in fulfilling their basic psychological needs.

Psychologists at the University of Rochester, in collaboration with Immersyve, Inc., a virtual environment think tank, asked 1,000 gamers what motivates them to keep playing. The results published in the journal Motivation and Emotion this month suggest that people enjoy video games because they find them intrinsically satisfying.

"We think there's a deeper theory than the fun of playing," says Richard M. Ryan, a motivational psychologist at the University and lead investigator in the four new studies about gaming. Players reported feeling best when the games produced positive experiences and challenges that connected to what they know in the real world.

The research found that games can provide opportunities for achievement, freedom, and even a connection to other players. Those benefits trumped a shallow sense of fun, which doesn't keep players as interested.

"It's our contention that the psychological 'pull' of games is largely due to their capacity to engender feelings of autonomy, competence, and relatedness," says Ryan. The researchers believe that some video games not only motivate further play but "also can be experienced as enhancing psychological wellness, at least short-term," he says.

Ryan and coauthors Andrew Przybylski, a graduate student at the University of Rochester, and Scott Rigby, the president of Immersyve who earned a doctorate in psychology at Rochester, aimed to evaluate players' motivation in virtual environments. Study volunteers answered pre- and post-game questionnaires that were applied from a psychological measure based on Self-Determination Theory, a widely researched theory of motivation developed at the University of Rochester.

Rather than dissect the actual games, which other researchers have done, the Rochester team looked at the underlying motives and satisfactions that can spark players' interests and sustain them during play.

Revenues from video games—even before the latest Wii, PlayStation 3, and Xbox systems emerged—surpass the money made from Hollywood films annually. A range of demographic groups plays video games, and key to understanding their enjoyment is the motivational pull of the games.

Four groups of people were asked to play different games, including one group tackling "massively multiplayer online" games—MMO for short, which are considered the fastest growing segment of the computer gaming industry. MMOs are capable of supporting hundreds of thousands of players simultaneously. For those playing MMOs, the need for relatedness emerged "as an important satisfaction that promotes a sense of presence, game enjoyment, and an intention for future play," the researchers found.

Though different types of games and game environments were studied, Ryan points out that "not all video games are created equal" in their ability to satisfy basic psychological needs. "But those that do may be the best at keeping players coming back."

Note: This story has been adapted from a news release issued by University of Rochester.

Link Between Insomnia And Hypersomnia, Depression In Children

According to a study published in the January 1st issue of the journal SLEEP, sleep-disturbed children are more severely depressed and have more depressive symptoms and comorbid anxiety disorders compared with children without sleep disturbance. To ensure the most effective care, parents of sleep-disturbed children are advised to first consult with the child's pediatrician, who may issue a referral to a sleep specialist for comprehensive testing and treatment.

The study, authored by Xianchen Liu, MD, PhD, and colleagues of the University of Pittsburgh, was conducted on 553 children with a depressive disorder. Out of this study group, 72.7 percent had sleep disturbance, of which 53.5 percent had insomnia alone, nine percent had hypersomnia alone and 10.1 percent had both disturbances. Depressed girls were more likely to have sleep disturbance than boys, but age had no significant effects.

Furthermore, the study found that across sleep-disturbed children, those with both insomnia and hypersomnia had a longer history of illness, were more severely depressed and were more likely to have anhedonia, weight loss, psychomotor retardation and fatigue than those with either insomnia or hypersomnia.

"We know that depression is associated with sleep problems. But what this study shows is that, in depressed youths, not all sleep problems are the same," said Liu. "Insomnia is the most common problem, but having a combination of insomnia and sleepiness is 'double trouble'. Youths having both of these had more severe depression than youths with just one sleep problem. This means that we should carefully ask depressed youths about the specific type of sleep problem they're having. It may also mean that we should think about different treatments to specifically target an individual's sleep problem."

Experts recommend that grammar school-aged children get between 10-11 hours of sleep a night to achieve good health and optimum performance, while children in pre-school should sleep between 11-13 hours a night.

SLEEP is the official journal of the Associated Professional Sleep Societies, LLC, a joint venture of the American Academy of Sleep Medicine (AASM) and the Sleep Research Society.

SleepEducation.com, a Web site maintained by the AASM, provides information about the various sleep disorders that exist, the forms of treatment available, recent news on the topic of sleep, sleep studies that have been conducted and a listing of sleep facilities.

Note: This story has been adapted from a news release issued by American Academy of Sleep Medicine.

Snakes in China 'predict quakes'

Scientists say the snakes smash into walls in an effort to escape

Scientists in China say they have developed a new way of predicting earthquakes - by observing erratic behaviour in snakes.

Experts at the earthquake bureau in Nanning, in southern Guangxi province, monitor local snake farms via 24-hour internet video links.

Scientists said the serpents can sense a quake from 120km (75 miles) away, up to five days before it happens.

They respond erratically, even smashing into walls to escape, scientists said.

"Of all the creatures on the Earth, snakes are perhaps the most sensitive to earthquakes," Jiang Weisong, director of the earthquake bureau in Nanning, told The China Daily.

The reptiles respond by behaving extremely erratically, he said.

"When an earthquake is about to occur, snakes will move out of their nests, even in the cold of winter. If the earthquake is a big one, the snakes will even smash into walls while trying to escape," he told the newspaper.

Nanning - an area prone to earthquakes - is one of 12 Chinese cities monitored by hi-tech equipment. It also has 143 animal monitoring units.

"By installing cameras over the snake nests, we have improved our ability to forecast earthquakes. The system could be extended to other parts of the country to make our earthquake forecasts more precise," Mr Jiang said.

China is frequently struck by earthquakes. In 1976, some 250,000 people died when the city of Tangshan was devastated by an earthquake.

EU welcomes Romania and Bulgaria

Romanians had something extra to celebrate on New Year's Eve

Romanians and Bulgarians have been marking their first day as European Union citizens, 17 years after the fall of communism.

Tens of thousands celebrated at midnight at concerts in the two capitals, Bucharest and Sofia.

The Romanian president said EU entry was an "enormous chance for future generations", while Bulgaria's leader said it was a "heavenly moment".

Their accession means the EU now has 27 members and half a billion people.

EU dignitaries attended the midnight celebrations in Bucharest and were flying on to Sofia on Monday for further ceremonies there.

EU Commission President Jose Manuel Barroso said: "In welcoming two new members in the family, we know our culture, our heritage, will be richer, our mutual ties and our economy will be boosted."

The day we are welcoming - 1 January 2007 - will undoubtedly find its place among the most important dates in our national history Georgi Parvanov Bulgarian president Romania optimistic on entry Q&A: EU enlargement

Romanian President Traian Basescu said: "It was hard, but we arrived at the end of the road. It is the road of our future. It is the road of our joy."

"We arrived in Europe. Welcome to Europe," Mr Basescu said on stage in University Square.

Earlier, the EU flag was raised outside the government headquarters in Bucharest to the European anthem, Beethoven's Ode to Joy.

On Monday morning young boys welcomed the new year in traditional style, cracking whips to chase away the evils of the past and ringing in the new with their bells.

In Sofia, a pyramid of light illuminated the sky, and thousands of people in Battenberg Square cheered as midnight struck.

In an emotional address to the nation, Bulgarian President Georgi Parvanov called the country's EU entry a "heavenly moment".

"The day we are welcoming - 1 January 2007 - will undoubtedly find its place among the most important dates in our national history," he said.

"But let's make it clear, our future success as a nation depends not on European funds and resources, but on our own work."

Border controls

On Monday morning everyday life appeared unchanged.

"I feel normally, like every other day. There is no difference, except may be the weather is fine today," said a passer-by in Sofia.

But Bulgaria has already had to make changes to comply with EU regulations.

Watch the EU map grow

Overnight it closed down part of its only nuclear power plant because of EU safety rules.

It also relaxed border controls at 15 crossings with EU members Greece and Romania, while strengthening them on its frontiers with Turkey, Serbia and Macedonia.

The EU's expansion means the bloc now stretches as far east as the Black Sea.

Romania and Bulgaria will now be subject to strict monitoring, to ensure they make more progress in the fight against corruption and organised crime.

They face export bans on certain foods, and Bulgaria has been warned that 55 of its aircraft could be grounded unless they reach EU safety standards.

Analysts say there is a risk that EU aid will be mis-spent, or just not taken up because the countries' institutions are too disorganised.

Bulgaria: Key facts Romania: Key facts

There are also fears that the countries' economies will fail to compete with the rest of the EU's once trade barriers come down.

Both Bulgaria and Romania are much poorer than the rest of the EU, with GDP per capita of about 33% of the EU average, compared with 50% in Poland.

Some Western European member states fear a flood of new immigrants, but officials in both countries say most of those who wanted to work abroad have already left.

Most of the 15 older EU member states have put in place restrictions on the free movement of workers from the two new members - though Finland and Sweden are two exceptions.